Hoisting mechanism



I. BENJAMINS.

HO|ST|NG MECHANISM.

APPLICATION FILED 11111.12. 1921.

1,399,73 Patented Dec. 13, 1921.

T /2 L 23 1?, l I Go 2 I FIG- amm/wtom PATENT OFFlt'ilrl.

ISRAEL BENJAMILNS, OF BROOKLYN, NEW" YORK.

HOISTING MECHANISM.

Application filed January 12, 1821.

To (all whom it may concern:

Be it known that 1, lemon. BENJAMINS, a citizen of the United States, residing at i rooklyn, in the county of Kings and State or New York, have invented a new and useioisting Mechanism, oi which the folis a specification.

invention relates to improvements in hoistin mechanisms, which may be used for dental and barbers chairs, as acks for automobiles, ea ages and wagons, also for seatfolds and .or sundry other purposes, for which the construction or" my hoisting mechanism is adapted, and. it consists in the novel features hereinafter more fully described.

objects of my improvement are:

First: To provide a collapsible hoisting mechanism with a stable base.

Second: To provide a saddle of constant length for the support of the load, said saddle being pivotally connected to the rods or bars supportinthe same.

'lhird: To avoid long screws or bolts subject to bending; and

Fourth: To have my mechanism simple, durable and inexpensive. I attain these objects by th mechanism illustrated in the accompanying drawing or by any mechanical equivalent or obvious modification of the same.

the drawings Figure l is a sioe view and l 2 an end view partly broken off at the lef end, both views be :rtly in crosssection a partly in eleva 3, 13 are bearings "for the support of the shaft 2% or the worms 25.

said bearings 13, 18 may be connected to the bearings 12 by suitable fastenings which are not shown in the drawings.

The bearings 12 may be likewise connected to the base plate 23.

M is a crank shown as connected to each of said worm gears 11 by means of the pins 15 and the keys 22, which fasten said pins to said worm gears and to each crank 1 which, if desired, may also be secured to said worm gears 11 by means of the pins 16, shown in Fig. 1 and omitted in Fig. 2.

17, 17 are two pairs of: connecting rods pivotally connected at their lower ends to said cranks l4 and at their upper ends to the sad- Specification of Letters Patent.

Patented Dec. 13, 1921.

Serial No. 436,?33.

die 20 by means the pins 18 and 21 respectively.

llach oi said pins :21 has connected thereto a sector of a gear wheel 19, which sectors in mesh with each other, thereby keeping the connecting rods l7, 17 at the same inclination with relation to a vertical or horizontal line passing through the center of each pin 21.

@ne of. he sectors 19 is shown with its th of the other are omitted for the sake of: clearness, and indicated by the pitch line of the teeth.

The shaft 534i terminates in the taper 26 which may be dete hably connected to a keywrench or lever for operating said worms 25, which may be secured to said shaft 24; or made in one therewith, if desired.

it is evir that by turning the worms one of which is right handed and the other lei't hantn" they will cause said worm gears 11. in opposite directions, thereby raising lowering the saddle 20.

T lowest position oi the sad le 20 is in i d and dash lines in i 1, also positions of the cranks 1 sears 3o e throu to bring the 1 saddle trom position to the lowest and vice "eeth may be omitted on part of cry of each worm gear, if desired, ovided thereon to make sears through the 5 e se:

longest arcs red ucn turner. ion for raising the load and in a counter clockwise direction for lowering the same.

Instead of the worm gears a pair of plain spur may be used, and the latter may be made to mesh with each other, when one oi the worms may be used and placed preferably at an angle to the plane or the gear in accordance with the rules of kinematics; a so the upper ends or" the connecting rods 17, instead or being directly connected to the saddle 2G, be connected instead to the lowe ends A ends of which may support the saddle 20, in which case the connecting rods 20 would cross each other and be pivotally connected to each other at the crossing point.

The upper bars of said pantograph may be open, (6. e. not crossed) at their upper ends, and their inclination to a vertical or horizontal line kept equal by means of the pair of sectors 19 as shown.

The sectors 19 are shown in Fig. 2 as inclosed by the saddle 20; but they may also be placed at one side thereof, if desired, thereby reducing the height of the saddle.

The worms 25 may be placed in contact with the upper part of the gears 11-, if desired, thereby permitting the connection of the ends of the two cranks of each gear by a single through pin 18 instead of the two studs, as shown in Fig. 2.

Many other changes could be made in the details of my hoisting mechanism without departing from the main scope of my invention. I do not, therefore, restrict myself to the details as shown; but I intend to include also all mechanical equivalents and obvious modifications of the same within the scope of my invention.

What I claim as my invention, and desire to secure by Letters Patent is:

1. In a hoisting mechanism a. pair of gears, a pair of worms in mesh therewith and adapted to rotate said gears in opposite directions, a crank connected to each of said gears and adapted to rotate therewith, a connecting rod pivotally connected at its lower end to each of said cranks and a support for a load at the upper ends of said connecting rods.

2. In a hoisting mechanism a pair of gears, a means for rotating said gears in opposite directions, a pair of connecting rods, pivotally connected at their lower ends to said gears and at their upper ends to a means for supporting a load, and a means for keeping the angle of inclination of said connecting rods equal to each other.

3. In a hoisting mechanism a pair of gears, a means for rotating said gears in opposite directions, a pair of connecting rods, pivotally connected at their lower ends to said gears and terminating at their upper ends in a pantograph, and a means for supporting a load at the upper end thereof.

4:. in a hoisting mechanism a gear, a worm in mesh therewith and adapted to rotate said gear and a connecting rod pivotally connected at its lower end to said gear and at its upper end to a support for a load, combined with a means for cooperating with said gear, said worm and said connecting rod to support the load in any position and to raise and lower said load.

5. In a hoisting mechanism a rotary member, a means for rotating the same and a connecting rod pivotally connected at its lower end to said member and at its upper end to a support for a load, combined with a means for cooperating with said member, said rotating means and said connecting rod to support the load in any position and to raise and lower said load.

ISRAEL BENJAMINS. 

